Sir Alex Ferguson has acknowledged that Manchester United's Ryan Giggs has set footballing records that will never be matched.

Giggs: Inspiration for young pros

The evergreen Manchester United midfielder will be making his 900th appearance if he plays some part in Thursday night's Europa League last-32 encounter with Ajax at Old Trafford.

He has played 140 times for the Red Devils since matching Sir Bobby Charlton's previous club record in the 2008 Champions League final win over Chelsea in Moscow.

So long has Giggs been going, team-mate Tom Cleverley cannot remember how young he was when he first became aware of the Welshman, who boasts a record 12 Premier League title medals.

"I can't remember exactly how old I was," Cleverley said. "But I remember pretending to be Ryan in the back garden."

In fact, Cleverley was just over 18 months when Giggs made his debut against Everton in March 1991, two seasons before the Premier League exploded into life.

He is the only player to have scored in all 20 seasons of the new league and has already agreed to extend his career by another season as he continues to defy the ageing process.

Ferguson said: "It is my personal view, and not everyone will agree with me because we all have our favourites, that even if you take away the longevity, being in the Premier League for as long as he has, achieving what he has; no other player will do it."

Few come close to being such a star performer, at such a high level, for such a long time.

The immediate comparison is with legendary Italian Paolo Maldini.

His first-team career with AC Milan spanned 24 years and he also made 900 appearances; 902 to be exact, before he quit, in 2009, a month before his 41st birthday.

Yet even there Ferguson feels there is a subtle difference that has to be taken into account when analysing the respective merits of two brilliant players.

"Obviously Maldini was a magnificent player but there is a distinction," said the United boss.

"Maldini was a defender and although in his case, he probably put in a lot of running as a full-back, wide (midfield) players have more work to do.

"It is amazing really. If you go back to Moscow, you are talking almost another 150 games further on.

"He keeps defying age. This season he has just been the same as he was back in Moscow. There is nothing changed from his performance level then as it is today."

In fact, Ferguson feels Giggs has improved.

The 38-year-old was already settling into a more central midfield role when that magnificent night for United at the Luzhniki Stadium came around.

Now Giggs is fully integrated, to the extent Ferguson thinks of him as a key operator in his engine room.

"His use of the ball has got better with age," said Ferguson.

"Changing his position to play in a more central area has given a different aspect to his game.

"We always remember what Ryan was famous for, going up and down that touchline, running at full-backs with great balance and speed.

"Today it is a different Ryan Giggs.

"He still has that change of pace and a wonderful balance but he is not as quick as he was 10 years ago and has looked at his game a different way."

So effective has that work been that the potential for Giggs reaching the magic 1,000 games mark was raised, even if it did raise an eyebrow from Ferguson, who has presided over every United game Giggs has played.

"One hundred games from now?" said Ferguson. "How old would that make him?

"Stanley Matthews played at 50 I suppose. We will just have to wait and see."

As they had a weekend off immediately after the first-leg triumph in Amsterdam, it is only now that Ferguson is being forced to wrestle with the thorny issue of a Thursday night turnaround to Sunday, which has proved problematic to many teams.

A trip to Norwich is hardly ideal so there is a chance Giggs will not have any more than a fleeting involvement on Thursday.

The same might have been said of Wayne Rooney, even without the sore throat that rules him out anyway.

And, as Ferguson points out, he has more than enough alternatives who do need some time on the pitch as his injury concerns start to ease.

"There are a lot of players who need a game: Nani, Young, Hernandez, Cleverley, Smalling, Jones," said the Scot.

"Those players will all play tomorrow and we hope to put a sprinkling of experience amongst it."